Outline

Objective: Skull base meningiomas involving the parasellar region and cavernous sinus often lead to clinically relevant compression of the oculomotor nerve in their cisternal or intracavernous course. Radical surgical removal of these tumors in the cavernous sinus may be associated with a high rate of irreversible cranial nerve deficits. In patients presenting with oculomotor nerve paresis, the effect of partial surgical decompression of the oculomotor nerve at the entrance into the cavernous sinus was not systematically evaluated so far. We report on a series of 16 patients with skull base meningiomas, where the effect of oculomotor nerve decompression at this site was analyzed.

Methods: All patients were operated through the pterional approach using microsurgical technique between April 2005 and April 2011. Surgical decompression of the oculomotor nerve at the entrance into the cavernous sinus was performed including opening of the dura at the entry point in all cases. Clinical data were collected prospectively including preoperative medical history, radiological, operative and histological findings and follow up records.

Results: Our series includes 12 women and 4 men with a mean age of 55.8 years (40–76 years). All patients presented with partial or complete oculomotor nerve palsy before surgery. Tumor compression of the oculomotor nerve at the entrance into the cavernous sinus was observed in all cases. Partial tumor removal was performed in 14 tumors, a subtotal resection in 2 patients. Partial or complete functional recovery of oculomotor nerve was observed in 12 out of 16 procedures (81.1%). The mean follow-up time was 22.3 months (6–65 months).

Conclusions: The majority of patients with skull base meningiomas compressing the oculomotor nerve in the interpeduncular cistern and entry into the cavernous sinus benefit from surgical decompression. Additional dural incision at the entry into cavernous sinus may provide further space and reduce the compressive effect of the tumor.